It is known that micromechanical acceleration and yaw rate sensors (inertial sensors) are manufactured on a single wafer as part of increasing the functional diversity thereof. If the internal pressure of caverns in which the sensors are situated is identical, considerable worsening of the sensor properties must be expected, e.g., with respect to sensor sensitivity or mechanical robustness of the sensors. It is therefore generally provided that different pressures are provided in the caverns of the acceleration and yaw rate sensors.
In this context methods are known in which a so-called getter is introduced into one of the caverns, which is activated after a capping process and is able to bind, or getter, the residual gas in the hermetically sealed cavern. It is possible in this way to manufacture caverns having different internal pressures in one manufacturing process. However, the described method is demanding in terms of the process technology and very cost-intensive.
German Application No. DE 10 2009 045 385 describes a method for sealing at least one trench of a micromechanical or electrical component, including the following steps: applying a lattice to the component over the trench to be formed, forming the trench beneath the lattice, and sealing the openings of the lattice over the trench by depositing a layer onto the lattice.